Found an article for calculating the UV Index, it takes into account elevation and cloud cover for the day which I think can be used to calculate back to the fluence rate (which from the short reading, is what this sensor is measuring [mW/cm2] although the formal unit is [W/m2]).

2) Get the current UV point based on mx + b. b is a positive offset of 1V (see page 3 of the data sheet “Output Voltage (Shading)”) so we need to subtract it out and the slope I calculated around 8.33 (someone check my math), so:

((#1 above) - 1.0) * 8.33

This will give you a result in [mW/cm2]. I’m not sure if this is a UV Index though, but judging that this sensor ranges between 0 and 15 [mW/cm2] I’d say this very well could be the UV Index.

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